11971440 has 120 divisors (see below), whose sum is σ = 43330560. Its totient is φ = 2944512.

The previous prime is 11971439. The next prime is 11971447. The reversal of 11971440 is 4417911.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11971447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8721 + ... + 9999.

It is an arithmetic number, because the mean of its divisors is an integer number (361088).

Almost surely, 2^11971440 is an apocalyptic number.

11971440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11971440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21665280).

11971440 is an abundant number, since it is smaller than the sum of its proper divisors (31359120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11971440 is a wasteful number, since it uses less digits than its factorization.

11971440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1311 (or 1302 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 11971440 is about 3459.9768785355. The cubic root of 11971440 is about 228.7610762351.

The spelling of 11971440 in words is "eleven million, nine hundred seventy-one thousand, four hundred forty".